1. Field of the Invention
This invention relates to a process for fixing several textile thicknesses along a line, and particularly an edge of a textile article, particularly but not exclusively underwear, and particularly an article such as underpants or bra with edges for which a tying is necessary.
2. Description of Related Art
It is known how to make a tying on the edge of openings of underwear articles, in other words to cover the edge by a textile ribbon folded in two overlapping the edge, this ribbon traditionally being sewn to fix it in place.
The objective nowadays is increasingly to avoid the use of sewn seams in underwear, both for the discomfort that sometimes results from sewing thread, and for aesthetic reasons.
It has already been proposed to fix several textile thicknesses along an edge by ultrasound using thermoplastic fibres (see WO 0228210) or thermogluing (see EP 1033084) or by processes using a combination of sewing and thermogluing (see U.S. Pat. No. 2,048,343). With the first two processes, there is a problem with precise positioning of the ribbon and the ribbon has the disadvantages of visible seams; an ordinary upper thread, for example made of cotton, is used for the seam with a thermoadhesive lower thread, for example made of cellulose acetate. The upper thread remains in place and is visible after the hotmelt operation.